text: /****************************************************************************
   * Title:     HD44780U LCD library
   * Author:    Peter Fleury <pfleury@gmx.ch>  http://tinyurl.com/peterfleury
   * File:	    $Id: lcd.c,v 1.15.2.2 2015/01/17 12:16:05 peter Exp $
   * Software:  AVR-GCC 3.3
   * Target:    any AVR device, memory mapped mode only for AT90S4414/8515/Mega
   *
   * DESCRIPTION
   *     Basic routines for interfacing a HD44780U-based text lcd display
   *
   *     Originally based on Volker Oth's lcd library,
   *     changed lcd_init(), added additional constants for lcd_command(),
   *     added 4-bit I/O mode, improved and optimized code.
   *
   *     Library can be operated in memory mapped mode (LCD_IO_MODE=0) or in
   *     4-bit IO port mode (LCD_IO_MODE=1). 8-bit IO port mode not supported.
   *
   *     Memory mapped mode compatible with Kanda STK200, but supports also
   *     generation of R/W signal through A8 address line.
   *
   * USAGE
   *     See the C include lcd.h file for a description of each function
   *
   *****************************************************************************/
  /* FRYZA: ADDED GLOBAL MCU SETTINGS */
  //#include "settings.h"
  
  #include <inttypes.h>
  #include <avr/io.h>
  #include <avr/pgmspace.h>
  #include <util/delay.h>
  #include "lcd.h"
  
  
  /*
  ** constants/macros
  */
  #define DDR(x) (*(&x - 1)) /* address of data direction register of port x */
  #if defined(__AVR_ATmega64__) || defined(__AVR_ATmega128__)
  /* on ATmega64/128 PINF is on port 0x00 and not 0x60 */
  # define PIN(x) ( &PORTF == &(x) ? _SFR_IO8(0x00) : (*(&x - 2)) )
  #else
  # define PIN(x) (*(&x - 2)) /* address of input register of port x          */
  #endif
  
  
  #if LCD_IO_MODE
  # define lcd_e_delay()  _delay_us(LCD_DELAY_ENABLE_PULSE)
  # define lcd_e_high()   LCD_E_PORT |= _BV(LCD_E_PIN);
  # define lcd_e_low()    LCD_E_PORT &= ~_BV(LCD_E_PIN);
  # define lcd_e_toggle() toggle_e()
  # define lcd_rw_high()  LCD_RW_PORT |= _BV(LCD_RW_PIN)
  # define lcd_rw_low()   LCD_RW_PORT &= ~_BV(LCD_RW_PIN)
  # define lcd_rs_high()  LCD_RS_PORT |= _BV(LCD_RS_PIN)
  # define lcd_rs_low()   LCD_RS_PORT &= ~_BV(LCD_RS_PIN)
  #endif
  
  #if LCD_IO_MODE
  # if LCD_LINES == 1
  #  define LCD_FUNCTION_DEFAULT LCD_FUNCTION_4BIT_1LINE
  # else
  #  define LCD_FUNCTION_DEFAULT LCD_FUNCTION_4BIT_2LINES
  # endif
  #else
  # if LCD_LINES == 1
  #  define LCD_FUNCTION_DEFAULT LCD_FUNCTION_8BIT_1LINE
  # else
  #  define LCD_FUNCTION_DEFAULT LCD_FUNCTION_8BIT_2LINES
  # endif
  #endif /* if LCD_IO_MODE */
  
  #if LCD_CONTROLLER_KS0073
  # if LCD_LINES == 4
  
  #  define KS0073_EXTENDED_FUNCTION_REGISTER_ON  0x2C /* |0|010|1100 4-bit mode, extension-bit RE = 1 */
  #  define KS0073_EXTENDED_FUNCTION_REGISTER_OFF 0x28 /* |0|010|1000 4-bit mode, extension-bit RE = 0 */
  #  define KS0073_4LINES_MODE                    0x09 /* |0|000|1001 4 lines mode */
  
  # endif
  #endif
  
  /*
  ** function prototypes
  */
  #if LCD_IO_MODE
  static void toggle_e(void);
  #endif
  
  /*
  ** local functions
  */
  
  
  /*************************************************************************
  *  delay for a minimum of <us> microseconds
  *  the number of loops is calculated at compile-time from MCU clock frequency
  *************************************************************************/
  #define delay(us) _delay_us(us)
  
  
  #if LCD_IO_MODE
  /* toggle Enable Pin to initiate write */
  static void toggle_e(void)
  {
      lcd_e_high();
      lcd_e_delay();
      lcd_e_low();
  }
  
  #endif
  
  
  /*************************************************************************
  *  Low-level function to write byte to LCD controller
  *  Input:    data   byte to write to LCD
  *         rs     1: write data
  *                0: write instruction
  *  Returns:  none
  *************************************************************************/
  #if LCD_IO_MODE
  static void lcd_write(uint8_t data, uint8_t rs)
  {
      unsigned char dataBits;
  
  
      if (rs) /* write data        (RS=1, RW=0) */
      {
          lcd_rs_high();
      }
      else /* write instruction (RS=0, RW=0) */
      {
          lcd_rs_low();
      }
  
      /* FRYZA: RW PIN NOT IMPLEMENTED */
      /*lcd_rw_low();*/    /* RW=0  write mode      */
  
      if ( ( &LCD_DATA0_PORT == &LCD_DATA1_PORT) && ( &LCD_DATA1_PORT == &LCD_DATA2_PORT ) && ( &LCD_DATA2_PORT == &LCD_DATA3_PORT ) &&
        (LCD_DATA0_PIN == 0) && (LCD_DATA1_PIN == 1) && (LCD_DATA2_PIN == 2) && (LCD_DATA3_PIN == 3) )
      {
          /* configure data pins as output */
          DDR(LCD_DATA0_PORT) |= 0x0F;
  
          /* output high nibble first */
          dataBits       = LCD_DATA0_PORT & 0xF0;
          LCD_DATA0_PORT = dataBits | ((data >> 4) & 0x0F);
          lcd_e_toggle();
  
          /* output low nibble */
          LCD_DATA0_PORT = dataBits | (data & 0x0F);
          lcd_e_toggle();
  
          /* all data pins high (inactive) */
          LCD_DATA0_PORT = dataBits | 0x0F;
      }
      else
      {
          /* configure data pins as output */
          DDR(LCD_DATA0_PORT) |= _BV(LCD_DATA0_PIN);
          DDR(LCD_DATA1_PORT) |= _BV(LCD_DATA1_PIN);
          DDR(LCD_DATA2_PORT) |= _BV(LCD_DATA2_PIN);
          DDR(LCD_DATA3_PORT) |= _BV(LCD_DATA3_PIN);
  
          /* output high nibble first */
          LCD_DATA3_PORT &= ~_BV(LCD_DATA3_PIN);
          LCD_DATA2_PORT &= ~_BV(LCD_DATA2_PIN);
          LCD_DATA1_PORT &= ~_BV(LCD_DATA1_PIN);
          LCD_DATA0_PORT &= ~_BV(LCD_DATA0_PIN);
          if (data & 0x80) LCD_DATA3_PORT |= _BV(LCD_DATA3_PIN);
          if (data & 0x40) LCD_DATA2_PORT |= _BV(LCD_DATA2_PIN);
          if (data & 0x20) LCD_DATA1_PORT |= _BV(LCD_DATA1_PIN);
          if (data & 0x10) LCD_DATA0_PORT |= _BV(LCD_DATA0_PIN);
          lcd_e_toggle();
  
          /* output low nibble */
          LCD_DATA3_PORT &= ~_BV(LCD_DATA3_PIN);
          LCD_DATA2_PORT &= ~_BV(LCD_DATA2_PIN);
          LCD_DATA1_PORT &= ~_BV(LCD_DATA1_PIN);
          LCD_DATA0_PORT &= ~_BV(LCD_DATA0_PIN);
          if (data & 0x08) LCD_DATA3_PORT |= _BV(LCD_DATA3_PIN);
          if (data & 0x04) LCD_DATA2_PORT |= _BV(LCD_DATA2_PIN);
          if (data & 0x02) LCD_DATA1_PORT |= _BV(LCD_DATA1_PIN);
          if (data & 0x01) LCD_DATA0_PORT |= _BV(LCD_DATA0_PIN);
          lcd_e_toggle();
  
          /* all data pins high (inactive) */
          LCD_DATA0_PORT |= _BV(LCD_DATA0_PIN);
          LCD_DATA1_PORT |= _BV(LCD_DATA1_PIN);
          LCD_DATA2_PORT |= _BV(LCD_DATA2_PIN);
          LCD_DATA3_PORT |= _BV(LCD_DATA3_PIN);
  
          /* FRYZA: EXPERIMENTALLY ADDED FOR ARDUINO UNO */
          _delay_ms(2);
      }
  } /* lcd_write */
  
  #else /* if LCD_IO_MODE */
  # define lcd_write(d, rs) if (rs) *(volatile uint8_t *) (LCD_IO_DATA) = d; else *(volatile uint8_t *) (LCD_IO_FUNCTION) = d;
  /* rs==0 -> write instruction to LCD_IO_FUNCTION */
  /* rs==1 -> write data to LCD_IO_DATA */
  #endif /* if LCD_IO_MODE */
  
  
  /*************************************************************************
  *  Low-level function to read byte from LCD controller
  *  Input:    rs     1: read data
  *                0: read busy flag / address counter
  *  Returns:  byte read from LCD controller
  *************************************************************************/
  #if LCD_IO_MODE
  /* FRYZA: RW PIN NOT IMPLEMENTED ==> DO NOT USE THIS FUNCTION */
  static uint8_t lcd_read(uint8_t rs)
  {
      uint8_t data;
  
      if (rs)
          lcd_rs_high();  /* RS=1: read data      */
      else
          lcd_rs_low();  /* RS=0: read busy flag */
      lcd_rw_high();     /* RW=1  read mode      */
  
      if ( ( &LCD_DATA0_PORT == &LCD_DATA1_PORT) && ( &LCD_DATA1_PORT == &LCD_DATA2_PORT ) && ( &LCD_DATA2_PORT == &LCD_DATA3_PORT ) &&
        ( LCD_DATA0_PIN == 0 ) && (LCD_DATA1_PIN == 1) && (LCD_DATA2_PIN == 2) && (LCD_DATA3_PIN == 3) )
      {
          DDR(LCD_DATA0_PORT) &= 0xF0; /* configure data pins as input */
  
          lcd_e_high();
          lcd_e_delay();
          data = PIN(LCD_DATA0_PORT) << 4; /* read high nibble first */
          lcd_e_low();
  
          lcd_e_delay(); /* Enable 500ns low       */
  
          lcd_e_high();
          lcd_e_delay();
          data |= PIN(LCD_DATA0_PORT) & 0x0F; /* read low nibble        */
          lcd_e_low();
      }
      else
      {
          /* configure data pins as input */
          DDR(LCD_DATA0_PORT) &= ~_BV(LCD_DATA0_PIN);
          DDR(LCD_DATA1_PORT) &= ~_BV(LCD_DATA1_PIN);
          DDR(LCD_DATA2_PORT) &= ~_BV(LCD_DATA2_PIN);
          DDR(LCD_DATA3_PORT) &= ~_BV(LCD_DATA3_PIN);
  
          /* read high nibble first */
          lcd_e_high();
          lcd_e_delay();
          data = 0;
          if (PIN(LCD_DATA0_PORT) & _BV(LCD_DATA0_PIN) ) data |= 0x10;
          if (PIN(LCD_DATA1_PORT) & _BV(LCD_DATA1_PIN) ) data |= 0x20;
          if (PIN(LCD_DATA2_PORT) & _BV(LCD_DATA2_PIN) ) data |= 0x40;
          if (PIN(LCD_DATA3_PORT) & _BV(LCD_DATA3_PIN) ) data |= 0x80;
          lcd_e_low();
  
          lcd_e_delay(); /* Enable 500ns low       */
  
          /* read low nibble */
          lcd_e_high();
          lcd_e_delay();
          if (PIN(LCD_DATA0_PORT) & _BV(LCD_DATA0_PIN) ) data |= 0x01;
          if (PIN(LCD_DATA1_PORT) & _BV(LCD_DATA1_PIN) ) data |= 0x02;
          if (PIN(LCD_DATA2_PORT) & _BV(LCD_DATA2_PIN) ) data |= 0x04;
          if (PIN(LCD_DATA3_PORT) & _BV(LCD_DATA3_PIN) ) data |= 0x08;
          lcd_e_low();
      }
      return data;
  } /* lcd_read */
  
  #else /* if LCD_IO_MODE */
  # define lcd_read(rs) (rs) ? *(volatile uint8_t *) (LCD_IO_DATA + LCD_IO_READ) : *(volatile uint8_t *) (LCD_IO_FUNCTION + LCD_IO_READ)
  /* rs==0 -> read instruction from LCD_IO_FUNCTION */
  /* rs==1 -> read data from LCD_IO_DATA */
  #endif /* if LCD_IO_MODE */
  
  
  /*************************************************************************
  *  loops while lcd is busy, returns address counter
  *************************************************************************/
  /* FRYZA: RW PIN NOT IMPLEMENTED ==> DO NOT USE THIS FUNCTION */
  static uint8_t lcd_waitbusy(void)
  {
      register uint8_t c;
  
      /* wait until busy flag is cleared */
      while ( (c = lcd_read(0)) & (1 << LCD_BUSY))
      { }
  
      /* the address counter is updated 4us after the busy flag is cleared */
      delay(LCD_DELAY_BUSY_FLAG);
  
      /* now read the address counter */
      return (lcd_read(0)); // return address counter
  }/* lcd_waitbusy */
  
  /*************************************************************************
  *  Move cursor to the start of next line or to the first line if the cursor
  *  is already on the last line.
  *************************************************************************/
  static inline void lcd_newline(uint8_t pos)
  {
      register uint8_t addressCounter = 0;
  
      #if LCD_LINES == 1
      addressCounter = 0;
      #endif
      #if LCD_LINES == 2
      if (pos < (LCD_START_LINE2) )
          addressCounter = LCD_START_LINE2;
      else
          addressCounter = LCD_START_LINE1;
      #endif
      #if LCD_LINES == 4
      # if KS0073_4LINES_MODE
      if (pos < LCD_START_LINE2)
          addressCounter = LCD_START_LINE2;
      else if ( (pos >= LCD_START_LINE2) && (pos < LCD_START_LINE3) )
          addressCounter = LCD_START_LINE3;
      else if ( (pos >= LCD_START_LINE3) && (pos < LCD_START_LINE4) )
          addressCounter = LCD_START_LINE4;
      else
          addressCounter = LCD_START_LINE1;
      # else
      if (pos < LCD_START_LINE3)
          addressCounter = LCD_START_LINE2;
      else if ( (pos >= LCD_START_LINE2) && (pos < LCD_START_LINE4) )
          addressCounter = LCD_START_LINE3;
      else if ( (pos >= LCD_START_LINE3) && (pos < LCD_START_LINE2) )
          addressCounter = LCD_START_LINE4;
      else
          addressCounter = LCD_START_LINE1;
      # endif /* if KS0073_4LINES_MODE */
      #endif  /* if LCD_LINES == 4 */
      lcd_command((1 << LCD_DDRAM) + addressCounter);
  }/* lcd_newline */
  
  /*
  ** PUBLIC FUNCTIONS
  */
  
  /*************************************************************************
  *  Send LCD controller instruction command
  *  Input:   instruction to send to LCD controller, see HD44780 data sheet
  *  Returns: none
  *************************************************************************/
  void lcd_command(uint8_t cmd)
  {
      /* FRYZA: RW PIN NOT IMPLEMENTED ==> DO NOT USE READ FUNCTION */
      /* lcd_waitbusy(); */
      lcd_write(cmd, 0);
  }
  
  /*************************************************************************
  *  Send data byte to LCD controller
  *  Input:   data to send to LCD controller, see HD44780 data sheet
  *  Returns: none
  *************************************************************************/
  void lcd_data(uint8_t data)
  {
      /* FRYZA: RW PIN NOT IMPLEMENTED ==> DO NOT USE READ FUNCTION */
      /* lcd_waitbusy(); */
      lcd_write(data, 1);
  }
  
  /*************************************************************************
  *  Set cursor to specified position
  *  Input:    x  horizontal position  (0: left most position)
  *         y  vertical position    (0: first line)
  *  Returns:  none
  *************************************************************************/
  void lcd_gotoxy(uint8_t x, uint8_t y)
  {
      #if LCD_LINES == 1
      lcd_command((1 << LCD_DDRAM) + LCD_START_LINE1 + x);
      #endif
      #if LCD_LINES == 2
      if (y == 0)
          lcd_command((1 << LCD_DDRAM) + LCD_START_LINE1 + x);
      else
          lcd_command((1 << LCD_DDRAM) + LCD_START_LINE2 + x);
      #endif
      #if LCD_LINES == 4
      if (y == 0)
          lcd_command((1 << LCD_DDRAM) + LCD_START_LINE1 + x);
      else if (y == 1)
          lcd_command((1 << LCD_DDRAM) + LCD_START_LINE2 + x);
      else if (y == 2)
          lcd_command((1 << LCD_DDRAM) + LCD_START_LINE3 + x);
      else /* y==3 */
          lcd_command((1 << LCD_DDRAM) + LCD_START_LINE4 + x);
      #endif
  }/* lcd_gotoxy */
  
  /*************************************************************************
  *************************************************************************/
  /* FRYZA: RW PIN NOT IMPLEMENTED ==> DO NOT USE THIS FUNCTION */
  int lcd_getxy(void)
  {
      return lcd_waitbusy();
  }
  
  /*************************************************************************
  *  Clear display and set cursor to home position
  *************************************************************************/
  void lcd_clrscr(void)
  {
      lcd_command(1 << LCD_CLR);
  }
  
  /*************************************************************************
  *  Set cursor to home position
  *************************************************************************/
  void lcd_home(void)
  {
      lcd_command(1 << LCD_HOME);
  }
  
  /*************************************************************************
  *  Display character at current cursor position
  *  Input:    character to be displayed
  *  Returns:  none
  *************************************************************************/
  void lcd_putc(char c)
  {
      /* FRYZA: RW PIN NOT IMPLEMENTED ==> DO NOT CALL LCD_WAITBUSY FUNCTION */
  
      /*    uint8_t pos;
       *
       *  pos = lcd_waitbusy();   // read busy-flag and address counter
       *  if (c=='\n')
       *  {
       *      lcd_newline(pos);
       *  }
       *  else
       *  {
       #if LCD_WRAP_LINES==1
       #if LCD_LINES==1
       *      if ( pos == LCD_START_LINE1+LCD_DISP_LENGTH ) {
       *          lcd_write((1<<LCD_DDRAM)+LCD_START_LINE1,0);
       *      }
       #elif LCD_LINES==2
       *      if ( pos == LCD_START_LINE1+LCD_DISP_LENGTH ) {
       *          lcd_write((1<<LCD_DDRAM)+LCD_START_LINE2,0);
       *      }else if ( pos == LCD_START_LINE2+LCD_DISP_LENGTH ){
       *          lcd_write((1<<LCD_DDRAM)+LCD_START_LINE1,0);
       *      }
       #elif LCD_LINES==4
       *      if ( pos == LCD_START_LINE1+LCD_DISP_LENGTH ) {
       *          lcd_write((1<<LCD_DDRAM)+LCD_START_LINE2,0);
       *      }else if ( pos == LCD_START_LINE2+LCD_DISP_LENGTH ) {
       *          lcd_write((1<<LCD_DDRAM)+LCD_START_LINE3,0);
       *      }else if ( pos == LCD_START_LINE3+LCD_DISP_LENGTH ) {
       *          lcd_write((1<<LCD_DDRAM)+LCD_START_LINE4,0);
       *      }else if ( pos == LCD_START_LINE4+LCD_DISP_LENGTH ) {
       *          lcd_write((1<<LCD_DDRAM)+LCD_START_LINE1,0);
       *      }
       #endif
       *      lcd_waitbusy();
       #endif
       */
      lcd_write(c, 1);
      //    }
  }/* lcd_putc */
  
  /*************************************************************************
  *  Display string without auto linefeed
  *  Input:    string to be displayed
  *  Returns:  none
  *************************************************************************/
  void lcd_puts(const char *s)
  /* print string on lcd (no auto linefeed) */
  {
      register char c;
  
      while ( (c = *s++) )
      {
          lcd_putc(c);
      }
  }/* lcd_puts */
  
  /*************************************************************************
  *  Display string from program memory without auto linefeed
  *  Input:     string from program memory be be displayed
  *  Returns:   none
  *************************************************************************/
  void lcd_puts_p(const char *progmem_s)
  /* print string from program memory on lcd (no auto linefeed) */
  {
      register char c;
  
      while ( (c = pgm_read_byte(progmem_s++)) )
      {
          lcd_putc(c);
      }
  }/* lcd_puts_p */
  
  /*************************************************************************
  *  Initialize display and select type of cursor
  *  Input:    dispAttr LCD_DISP_OFF            display off
  *                  LCD_DISP_ON             display on, cursor off
  *                  LCD_DISP_ON_CURSOR      display on, cursor on
  *                  LCD_DISP_CURSOR_BLINK   display on, cursor on flashing
  *  Returns:  none
  *************************************************************************/
  void lcd_init(uint8_t dispAttr)
  {
      #if LCD_IO_MODE
  
      /*
       *  Initialize LCD to 4 bit I/O mode
       */
  
      if ( ( &LCD_DATA0_PORT == &LCD_DATA1_PORT) && ( &LCD_DATA1_PORT == &LCD_DATA2_PORT ) && ( &LCD_DATA2_PORT == &LCD_DATA3_PORT ) &&
        ( &LCD_RS_PORT == &LCD_DATA0_PORT) && ( &LCD_RW_PORT == &LCD_DATA0_PORT) && (&LCD_E_PORT == &LCD_DATA0_PORT) &&
        (LCD_DATA0_PIN == 0 ) && (LCD_DATA1_PIN == 1) && (LCD_DATA2_PIN == 2) && (LCD_DATA3_PIN == 3) &&
        (LCD_RS_PIN == 4 ) && (LCD_RW_PIN == 5) && (LCD_E_PIN == 6 ) )
      {
          /* configure all port bits as output (all LCD lines on same port) */
          DDR(LCD_DATA0_PORT) |= 0x7F;
      }
      else if ( ( &LCD_DATA0_PORT == &LCD_DATA1_PORT) && ( &LCD_DATA1_PORT == &LCD_DATA2_PORT ) && ( &LCD_DATA2_PORT == &LCD_DATA3_PORT ) &&
        (LCD_DATA0_PIN == 0 ) && (LCD_DATA1_PIN == 1) && (LCD_DATA2_PIN == 2) && (LCD_DATA3_PIN == 3) )
      {
          /* configure all port bits as output (all LCD data lines on same port, but control lines on different ports) */
          DDR(LCD_DATA0_PORT) |= 0x0F;
          DDR(LCD_RS_PORT)    |= _BV(LCD_RS_PIN);
          DDR(LCD_RW_PORT)    |= _BV(LCD_RW_PIN);
          DDR(LCD_E_PORT)     |= _BV(LCD_E_PIN);
      }
      else
      {
          /* configure all port bits as output (LCD data and control lines on different ports */
          DDR(LCD_RS_PORT)    |= _BV(LCD_RS_PIN);
          DDR(LCD_RW_PORT)    |= _BV(LCD_RW_PIN);
          DDR(LCD_E_PORT)     |= _BV(LCD_E_PIN);
          DDR(LCD_DATA0_PORT) |= _BV(LCD_DATA0_PIN);
          DDR(LCD_DATA1_PORT) |= _BV(LCD_DATA1_PIN);
          DDR(LCD_DATA2_PORT) |= _BV(LCD_DATA2_PIN);
          DDR(LCD_DATA3_PORT) |= _BV(LCD_DATA3_PIN);
      }
      delay(LCD_DELAY_BOOTUP); /* wait 16ms or more after power-on       */
  
      /* initial write to lcd is 8bit */
      LCD_DATA1_PORT |= _BV(LCD_DATA1_PIN); // LCD_FUNCTION>>4;
      LCD_DATA0_PORT |= _BV(LCD_DATA0_PIN); // LCD_FUNCTION_8BIT>>4;
      lcd_e_toggle();
      delay(LCD_DELAY_INIT); /* delay, busy flag can't be checked here */
  
      /* repeat last command */
      lcd_e_toggle();
      delay(LCD_DELAY_INIT_REP); /* delay, busy flag can't be checked here */
  
      /* repeat last command a third time */
      lcd_e_toggle();
      delay(LCD_DELAY_INIT_REP); /* delay, busy flag can't be checked here */
  
      /* now configure for 4bit mode */
      LCD_DATA0_PORT &= ~_BV(LCD_DATA0_PIN); // LCD_FUNCTION_4BIT_1LINE>>4
      lcd_e_toggle();
      delay(LCD_DELAY_INIT_4BIT); /* some displays need this additional delay */
  
      /* from now the LCD only accepts 4 bit I/O, we can use lcd_command() */
      #else /* if LCD_IO_MODE */
  
      /*
       * Initialize LCD to 8 bit memory mapped mode
       */
  
      /* enable external SRAM (memory mapped lcd) and one wait state */
      MCUCR = _BV(SRE) | _BV(SRW);
  
      /* reset LCD */
      delay(LCD_DELAY_BOOTUP);               /* wait 16ms after power-on     */
      lcd_write(LCD_FUNCTION_8BIT_1LINE, 0); /* function set: 8bit interface */
      delay(LCD_DELAY_INIT);                 /* wait 5ms                     */
      lcd_write(LCD_FUNCTION_8BIT_1LINE, 0); /* function set: 8bit interface */
      delay(LCD_DELAY_INIT_REP);             /* wait 64us                    */
      lcd_write(LCD_FUNCTION_8BIT_1LINE, 0); /* function set: 8bit interface */
      delay(LCD_DELAY_INIT_REP);             /* wait 64us                    */
      #endif /* if LCD_IO_MODE */
  
      #if KS0073_4LINES_MODE
      /* Display with KS0073 controller requires special commands for enabling 4 line mode */
      lcd_command(KS0073_EXTENDED_FUNCTION_REGISTER_ON);
      lcd_command(KS0073_4LINES_MODE);
      lcd_command(KS0073_EXTENDED_FUNCTION_REGISTER_OFF);
      #else
      lcd_command(LCD_FUNCTION_DEFAULT); /* function set: display lines  */
      #endif
      lcd_command(LCD_DISP_OFF);     /* display off                  */
      lcd_clrscr();                  /* display clear                */
      lcd_command(LCD_MODE_DEFAULT); /* set entry mode               */
      lcd_command(dispAttr);         /* display/cursor control       */
  }/* lcd_init */
  